The invention relates to a hydraulic torsional vibration damper which is characterized in that the secondary mass is guided by a pair of slotted plastic flange sleeves with an L-shaped cross-section. The damper is characterized in that the butt joint is closed by a bridge temporarily formed onto it that will either break or deform in an elastic plastic manner when thermal length changes occur, thereby allowing transport of the sleeves in a pile and an automatic assembly of the damper.
